The objective of the study is to evaluate the impact of the milk-based nutrient-rich bar, specifically the effect of its fortification with zinc, iodine, vitamins A and D and calcium on nutritional status of school children, focusing on vitamin A and, zinc, iodine, calcium and iron status, and on their cognitive performances.

Design: double-masked randomized control trial Place: three schools in South Vietnam, Can Tho district, South Vietnam Subjects: School children aged 6 to 10 years old, from first grade to third grade of 3 primary schools.

Duration of intervention: 6 months (consumption of Goody or "control bar")

Study groups: 2 groups:

Group 1: children will receive micronutrient enriched milk bar. Group 2: children will receive the same milk-based food except for the micronutrient fortification.

Inclusion Criteria:

• pupil in one of the 2 selected schools, in grade 1 - 3
• weight for height > -3 z-scores
• hemoglobin concentration > 70 g/L

Exclusion Criteria:

• weight for height < -3 z-scores
• hemoglobin concentration <= 70 g/L